Jack mechanism



April 28, 1931.

W. N. SQUIRES' JACK MECHANISM Filed'Sept. 20, 1927 5 Sheets-Sheet l I I..." n l Jaffe/M07" 59u@ azZZw* 4010251/ ZZZM/ @V/WM W. N. SQUIRES JACK MECHANISM April 28, 1931.

5 Sheets-Sheet 2 Filed Sept. 20, 1927 April 28, 1931.

w. N. SQUIRES JACK MECHANIsM Filed sept. 20, 1927 5 Sheets-Sheet 3 JACK MECHANISM Filed sept. 20, 1927 5 Sheets-Sheet 4 Ngus K *fami/afar @hmm April 28, 1931. `w N, sQUlREs 1,802,790

I JACK MECHANISM Filed Sept. 20, 192'? 5 Sheets-Sheet 5 g8 /Zz i A l wl v *Patented Apr. 2,8, 19-31 UNITED STATI-is WIIIBUR N. soUIREs, or JOI'LIN, MISSOURI, AssIGNoR 'ro HYDRAULIC DEEI WELL v PUMP ooMPANY, or JOBLIN, MISSOURI, A CORPORATION or MISSOURI JACK MEcHANIsM pplication iled September 20, 1927. Seria1 No. 220,728.

My present inventionrelates to the art of?.

pumping and more particularly it is` applicable to the pumping of deep Wells such as are encountered in-oil fields though the invention is not to be restricted to that particular field. It has been proposed heretofore to raise the liquid from a Well by reciprocating columns of liquid one of .Which is the discharge line such a system being disclosed in my copending application, Serial No.

' 159,896, filed January 8, 1927.

The present invention is particularly directed to the pulsator or jack mechanism for reciprocating these `columns of liquni to operate the pump inthe Well and to discharge the quantity of oil brought up. at each stroke of the pump. I

One of the obstacles encountered in the pumping of oil Wells by a pumping mechaso nism of this class is the evolution of gas. In many cases gas is evolved in the Well and escapes up through the liquid standing 1n the casing. This gas which is dravvno at the casing head is not appreciably Involved in pumping ofthe oil from the vvell. 'Ihe gas which Irefer to is that which' is evolved after the oil enters the pump or the pipe lines. In many cases the oil is saturated With gas and the agitation which is caused by the pumping action releases the gas in thepump-or in the reciprocating columns. Also the liquid usually comprises some light or volatile constituents which tend to volatilize under release of pressure. .'25 The gas or vapor which thus or otherwise finds its Wayinto the pump presents diiiiculty first in the pump cylinder and second inf the reciprocating columns. Consider the case of a pump disposed in'a deep Well and 40 lifting oil against a head of the order of 1000# per sq. in. If the pumping cylinder should be filled with gas .and a compression stroke ismade obviously the gas @must be compressed to a pressure suiiiciently above the head to lift the discharge check valve otherwise the gas cannot be driven out of the cylinder and the pump would become air Lound.V This means that the compression ratio i. e. the ratio of displacement space to clearance space must be made great enough to i'sure vexpulsion of the gas a ainst any head encountered by the pump. IJreferably I provide a pump cylinderof relatively great length as compared to the'bore to secure the desired compression ratio Without being required `to Work to close'dimensions on the intake and discharge valve passages and pockets. By this means I am able to` pump out any gas which enters the pump cylinders.

The gasisthen dischargedintothe discharge line colmn Where it presents a dierent problem. The discharge stroke of the pump cylinder is made by applying pressure to one side of' themotor piston through the inner column of oil Which remains substantially the same throughout the pumping operation.

The suction stroke is made by applying pressure to the other side of the motor piston through the outer column of oil which serves also as the discharge line. While a certain amount of .gas may be evolved from the inner or high pressure column and provision must be made to.get rid of it, the real problem isto get rid of the gas in the discharge or 10W pressure columns The gas in the discharge or low pressure lcolumn tends to bubble up .by gravity and'it'expands as it rises but this takes time and the pump may make many.

strokes before the particular body of vgas can I of the pump cylinder.

this stroke.

strokes of thepump evenif considerable gas is evolved in the oil being pumped.

In the preferred form of the pump the pump piston is single acting. The rod passes through a packing which closes the one end O11 the discharge stroke the pressure on the inner or high pressure column must be. great enough to discharge the fluidcontents of the pump cylinderagainst the full head of the discharge. This may require very high pressure. At the same time the piston draws a vacuum in the closed end of the pump cylinder.

.Then when the intake stroke is to be made.-

the pressure toV be imposed upon the discharge oriow pressure column n eed `be only great enough to draw in a charge of liquid fy the pump structure to employ a diiierential motor piston presenting a `greater areato thev pressure in the discharge line than to the pressure in the innerline. Thus, by presenting differential areas to the two columns, the return stroke maybe made without requiring any pressure to be imposed on'the discharge column' than the actual head of the column.l

I may, if desired, depend upon a difference in area between the -motorpiston and the pump piston for making the suction stroke.-

This modified form of structu-re may be advantageously employed when the gasv content' 1s low .and the discharge column is fairly conj I a predetermined maximum, one1n one directinuous.

My present invention provides an automatic valve mechanism operable at each stroke 'of each column to releaseasuch gases as rise to the top of the column. Preferably this release occurs'during the up stroke of4 the column and during the 'initial part of l the down stroke although obviously such release might be secured at any part of the stroke. While the operation of this gas release valve in .one or both' cylinders is automatic while the machine is in operation, the

length of time during which the valve is held open may be adjusted t0 meet the particular conditions of a particularwellfthe gases and any liquid released by this gas release valve are conducted to 'a receiving tank which receives the liquid discharged from the s'ys` tem. Thus this gas discharge valve may be employed in eliminating not only gases but also to`controlthe effective stroke-of the actuating pistons in the-head mechanism.

.drawings 1 tion.

The use-of this valve is advantageous t'o secure the proper displacement 'of the corre# spending pulsator piston. The displacement .required may va ryvdepending upon the co1 n-'1 pressibility of the working medium andthe expansibility of the line underpressure.V The compressibility of the working medium depends upon its composition and the amount of gas which itinay contain. The expansi-v.

bility of the power lines depends upon the pressure to whichthey are subjected.

I therefore, preferably construct 'the head mechanism with a'length of stroke in excess of the actual displacement required to secure the full stroke of the motor mechanism of the pump in thcwell and by adjusting the point of ,closing of the gas release valve I make the displacement of the .operatingpiston in the head mechanism correspondto the requlred displacement of the motor mechanism in the well.V -I f In the op'eration'of the -head mechanismand the pump -as'I shalldescribe more in detail later, ythe jack mechanism and the pump may be out of time andl an excess of, liquidmay be trapped under the operating' piston so -that operation of the jack mechanism would tend to place an excessivepressure onthe connect ing lines, the valves and themotor mechanism I of the pump, particularly on starting up the operation of a system of this character, and 4I therefore provide an'\ automatic transfer or release between the reciprocating columns in each direction.. so that 1f, forvexample, the

-system should be started with the head mechanism out of phase ,with the pumping mechanism in the well, these two mechanisms would in a few strokes synchronize with each other and proceed in an orderly fashion.

l The manner in which Isecure this synchronizin g function is to employ a pair of conduits between the two columns and dispose in each of them a pressure 'release valve oper-ating at tion between the columns and the other in the opposite direction between the columns. Ob-

viously these valves may' be disposed side by Y to permit the discharge of the'excess of. liquid which is discharged through the di'scharge line on -the discharge stroke of the pump. For thispurpose Iprovide an automatic let off valve-for` discharging the proper.

quantity of oil froml the discharge column j corresponding to the amount 'pumped on the discharge stroke.

My inventionprovides a jack mechanism includingthe above features and certain otherfeatu'res of novelty which will be apparent from the .following detailedv specification and which form a part ofl my' appliea- In order to acquaint those skilled in the art with the manner of constructing and operating a device according to my invention, I shall describe in connection with the accompanying drawings a specific embodiment of Fig. 5 isa side view taken from the left ofv Fig. 4;

Fig. 6 is an enlarged view showing in elevation the adjustable trip mechanism for the gas release valve; y

Fig. 7 is a longitudinal sectional view taken through the plunger and co'ntrol mechanism for the gas release valve` on the line 7-7 of Fig. 6;

Fig. 8 is a top Jplan View of the 4structure shown in Fig. 7;

Fig. 9 is a diagrammatic view of a detail, namely, the catch or detent for holding the gas release valve operating eccentric;

Fig. 10 is a diagrammatic plan view of the pipe connections between the jack and the well; and

Fig. 11 is a side elevational view of a modified detail, namely, the adjustable trip for- 'filled with liquid cpnstituting operating columns and the pipe 3 and conduit 4 constituting the discharge lineiof oil pumped from the well to a discharge line 9 Which leads to a suitable receiver or tank into which the oil is pumped. The outer pipe 3 is adapted to'receive the oil discharged Vfrom the pump cylinder 1() through the discharge check valve 11 and the -interior of pipe 3 communicates with the interior of the motor cylinder 12 below the motor piston 13, which motor piston is connected by a suitable rod 14 with the pump piston' 15. The bottom o-f the pumpcylinder 10 connects through an inlet check valve 16 and inlet passageway 17 with the oil in the well. The upper end of the pump cylinder 10 is closedolf above the piston 15 through the medium of a packing andvgland 18 so `that the upper end of the cylinder 10 is closed against the -entry or. exit of the fluid tobe pumped, provision being made as explained in my copending application, Serial No. 219,922, tiled Sept. 16, 1927, for evacuating any lluid which may enter this close space by leakage or accident.v The upper end ol the motor cylinder above the piston 15 communicates with the inner pipe G.

The cylinders 5 and 8 have therein suitable pistons or plungers 19 and 20 adapted to be reciprocalned alternately to reciprocate the liquid columns contained in the pipes and conduits above referred to.

The mechanism for reciprocating these plungers 19 and 2O includes a shaft 21 having the. crank discs G5 and, (5G employing crank pins 24 and 25 connected by suitable connecting rods 26 and 27 tothe plungers 19 and 20, respectively. It can now be seen by reference to Fig. 1 that as the plungers 19 and 2O are plunged up and down in opposite phase the liquid columns contained in the Conner,` tions 3, 4, 6 and 7 will be synchronously reciprocated. Such reciprocation lof the liquid columns moves the motor piston 13 up and down to reciprocate the same in phase with the jack mechanism, thereby operating thev pump piston 15 lo draw in and expel successive charges of liquid from the well. Upon each downward stroke of the pump piston l5 fluid is ,discharged from the pump cylinder past the check valve 10 against the head of the discharge column at that point and synchronously with said discharge a let-olf valve 28 `is operated by means of al push rod 29 and cam 30 on the crank shaft 21 to permit the discharge of excessliquid out by way of the pipe 31, valve 28 and discharge connection 9 to the receiving tank.

The valve 28 closes at'the same time that the plunger 19 begins to descend so that pressure imposed on the discharge column forces the piston 13 upwardly in the motor cylinder 12 and raising the pumping piston 15 to draw in a fresh charge of iuid from the Well. At the same time that the motor piston 13 is raised the jack plunger 20 is also raised so that the liquid displaced by the motor piston 13 finds the proper space in the jack cylinder 8.

The lines 4 and 7 are connected bycross connections 32 and 33. 'These cross connections include the transfer valves 34 and 35, respectively. The transfer valves are'spring loaded check valves, the spring loading being under suitable control to permit the valves to pop open in one direction when the pres-- i ing in the valve 35, vsaid valve would open and the deficiency which existed in the other to nation `of the 'displacement of the jack pispermit liquid to be transferred from the line 7 to the line 4. In a similar manner if the pressure in the line 4 exceeds the spring loading of the valve 34 liquid will be transferred from the line 4 to the line 7. Assume that the mechanism of the pump 1 is outof phase with the head or jack mechanism, as shown-for in- -stance in Fig. l. 'l`lieplunger 19 begins to descend and the plunger 20 begins to rise. vSince the pliingers of the pump are out of tiinewith the plungers of the ackcmechanisin the motor piston 13 will reach the end of it',1 stroke before the jack plungerA 19 has descended to the full limit of its stroke. The liquid in the line 4 will thereupon have no escape and the pressure rising above the value of the spring loading of the valve 34 opens said valve and liquid moves through the cross connection 32 into the high pressure line 7'.

Theliqud which is thus transferred from one line to the other not only removes the excess which existed in the one lin??l but supplies bring'about phase synclironisin between the jackmechanism and the pump mechanism.

Obviously, if the two mechanisms-were out of phase in the other direction, namely, if there were an excess of fluid in the `p ipe 7 liquid would be transferred from the pipe 7 to the pipe 4 through the opening of the loaded check valve 35.

With the above general explanation of the functions of the apparatus ,I shall now de-A scribe more in detail the structure of the jack mechanism and its further functions, particularly in connection with the 'release vof gasV from the operating columns and the determitons for correct operation of the pump.

The jack mechanism shown 1n the general views of Figs. 4 and 5 comprises two side frame members 40 and 41 provided at theirlower -ends with pedestals er feet 42 and 43 adapted to rest upon a suitable foundation..l

These sides frames are connected together by cross frame members 44 and45 and the pedestals 42 and 48 are .tied together by a cross brace 45. A portion of the discharge connection 31 is supported on thecrossbraee 46l and the oil discharge valve 28 is contained in said portion of the pipe 31.

Pairs of arcuate brackets 4 7, 47 and 48, 48 are formed integrally with the side frames 40 and 41, respectively, and these support the frames of the cylinders 5l and 8, respectively.

nections through the heads 55 and 56 to the pipe lines 4 and 7, respectively.

The cylinders 5 and 8 have the operating plungers 19 and 20 working therein. The plungers 19 and 2O have cross heads 59 and 60 formed integral with the upper ends, these 61 and 62, which are preferably formed integral with the side frame members 40 and 41. The cross heads59 and 60 are connected hy suitable wrist pins 63 and 64, to connecting rods 26 and 27 respectively. These 'connecting rods in turn are connected to crank pins 24 and 25, the crank pins being adjustably seated-in holesin the crank discs 65 and 66. The holes in the crank dises 65 and 66 are placed at various radial distances from the center of the crank" shaft 21 so that the stroke of the pistons' or plungers 19 and 20 may be adjusted. These holes are shown at 67 in Fig. 5 in disc-66. A corresponding series of holes iso provided in the disc 65l holes at the same radial distance being spaced 180 apart so as to maintain synchronism.

The crank shaft 21 has suitable journal bearings at. 68 and 69 at the top of the frames 4() and 41. respectively. A'bull-gear 70 is splined onto the crank shaft 421 and it is driven by a pinion 71 on thecounter shaft 72. The counter shaft. 72. has suitable bearings cross heads being guided in suitable guides at 73 and 74 on the frames 40 and 41 and it has in turn a. bull gear 75 keyed thereto, which is driven by the power pinion 77 keyed to the shaft 78 has journal bearings as indicated at 79 in the frame members and said power shaft 78 extends-off laterally to makesuitable driving connection with an electric motor, gasoline engineer other source of power for driving the jack. Preferably a belt pulley is mounted on the shaft 78 and the same is drivpower or 'drive shaft 78. The power. or drive en by a belt from an electric motor, gasoline engine or the like.

- The hull 'gear 70 has a valve operating cam 8O adjustably bolted to one side thereof asA by means of the bolts or cap screws 81, suitable slots being provided in said cam 80 to permit of lar'igular adjustment of the cam 80 about the shaft 21. The upper end of the thrust rod 29 which operates the discharge valve 28 is provided with a follower in the form of a roller 82 held against the' face of the cam 80 as by means of the compression spring 88. The thrust rod 29 is suitably'- guided in the crossframe members 44 and 45 and -the upper end is also guidedby a bracket 84, which is attached to the gear cover for the bull wheel 70,'which cover for'the sake of clearness has been omitted from the drawing.

The cam 8O has a suitable lift 0r .dwell for depressing the push rod 29 Aat the beginning of the downward stroke of the plunger 20` which downwardstroke of the plunger 20 performs the discharge stroke of the pump the well.

' for compensatingfor the difference in displacement required for the two strokes of the pump, but it will be apparent that less displacement is required theoretically to raise the plunger 1'3 than to depress the same. l

It can now be seen that by applying power to the drive shaft 78 the counter-shaft 72 is actuated and this in turn drives the-crank shaft 21 reciprocating the pistons 19 and 20 to depress the fluid column in one pipe while the Huid' column in the other pipe rises and vice versa. Also, upon each stroke of the piston 20 the let-'off or discharge valve 28 -is opened to permit the discharge of oil into the receiver or reservoir into which it is pumped.

As previously explained it is necessary to make provision for releasingl the gas which is evolved in either or both columns during;

normal operation ofthe device. To this end the plungers 19 and 20 are provided with gas release valves as indicated at 86 and 87 in Fig.

1.' These gasrelease valves and their `con' trolling" mechanism are the same for both suitable guidin plungers and hence the description of one of them will suffice for b oth.

Referring now to Figs. 6, 7 and 8', it will be seen that the plunger20 is drilled longitudinally to provide a bore 9 1 in which there is disposedv a valve operating rod 88 having` wings 89 at its upper end and guiding wrngs at 90 along its central portion. The lower end of the plunger "20 is counterbored :and a hardened valve seat member 92 is pressed into place in saidcounterbore to 4form a seat for the ball valve 87.l

A- perforated cap member 93 is threaded into the lower end of the plunger Vmember 20 fand it contains a spring 94 tending`to seatithe ball 87 upon the seat member 92. The cap member 93 thus forms a cage for the spring and the Valve, but dile to the longitudinal perforations therethrough-fluid is permitted to pass freely through saidy cage vwhen the valve 87 is thrust from its seat byrod 88. The longitudinal bore 91 communicates with an outlet passageway-95 at the upper end of the plunger 20, this outlet passageway lterminating in a pipe socket into which is threaded the nipple 96. The nipple 96 communicates with an elbow 97 and the elbow 97 in turn is connected to la pipe 98 which@ has a flexible hose 99 connected thereto, this hose leading through a valve 100 to a-common v gas discharge pipe 101 which leads to the top of the reservoir or receiver into which oil is-pumped or to anyother suitable receiving connection. v' f The plunger 19 likewise has the same construction and empio s a similar flexible hose connection 99 lea ing through a control valve 100 .to the same gas discharge pipe 101.

rI`he lmeans for operating the valve push rod 88 comprises a cam shaft 103having a cam`104 thereupon disposed in a recess 105 in the metal of the cross head 60 above the plunger 20, the bore 91 continuing past the passageway 95 into said recess .105 so that the head of the pushrod 88 engages the cam member 104, the valve spring 94: being strong enough to raise the valve from its seatand to maintain at other times the push rod 88 in engagementwith the cam 104;. An antifriction bushing '1 06 is threaded lin the-open e'nd of the Apocket or recess 105 to form vav bearing'- for the camshaft 103. The linner end-of the cam shaft 103.. has la bearing inthe body ofthe cross head- 601 The 'bearing bushing 106 is vcounterbored to form a' gland pocket for vreceiving packing 107 heldin. place by a gland follower 108.

The cam shaft103 bears at its outer'end an :operating arin 109, said arm bearing at, its outer end a roller 110 for the purpose ofv engaging suitable controlling members lor Aguldes, as will be explained in detail later.

A helical torsion spring 11'1has its outer end connected as by. means of the pin 112 to the arm 109 and it has its inner end secured to alight .metal bracket` 113, this bracket being U-shaped and having its end secured tothe sides ofthe cross head member, as will be apparent from Fig. 8. The cam shaft 103 passes through lan 'opening in .said bracket and the 'helical spring which surrounds -the shaft 103 has its'inner end securedas by means ofthe pin 114: to saidv bracket 113.i it@ The spring 111 tends at vall times to rotatei the crankarm 1( )9and sl 1aft 103 in a eloeky wise directionto permit the valve spring943/,f to vclose'thevalve 87. vIn all the positions of the'valve 87 duringthe downward stroke it is closed so that pressure may be exerted upon-the corresponding liquid column.

` The hub 'of the arm 109 is notched as indil cated `at 115 inFig. 6, and this notch is adapted to be engaged by the nose 116 of' a pawl member 117 This pawl member 117 is 1 20' mounted on a stud 118 supported on. the cross head 60. The rear end of the pawl117 has a shoulder 119 which is adapted-to be engaged by fa trip adjustably disposed in the path of the same for tripping`4 the hook 116 out of the4 notch 115'to .permit the spring 113 to turn theeam shaft so that the valve 87 may be closed.

The means for rotating the cam shaft and arm 109 so that the nose or hook -116of the nal grooves 123 and inturned flanges 124 along their outer edges. The flange 124 at the left side of Fig. 6 is continuous throughout the lengths of said side frame member 120, whereas the corresponding flange 124 on the right side of Fig. 6 is cut away throughout the central part of the correspondingl frame member 121. A cover plate 126 bears against the inside of the flanges 124 and steel strips rectangular in cross section, shown at 127 and 128 lie within the grooves 123 against the margins of the cover plate 126 and these strips and the margins of the plate 126 are clamped to the inside of the flanges 124 by the cap'sc-rews 129. The roller 110 on the arm 109 isadapted to be brought into engagement with said strips 127 and 128, as will be apparent later. The pawl 1-17 is counter-weighted so that the nose 116 thereof tends at all times to enter the notch 115 when said notch is brought into register. The pawl 117 is tripped out by an adjustable trip member 130. This adjustable trip arm constitutes a pivoted member having a shoulder 131 normally lying in the path of the shoulder 119 on the rear end of the pawl 117. "The trip 130 is mounted pivotally on a stud 132 which issecured upon the adjustable trip plate 133, this plate being provided-with a series of slots 134, through which project corresponding studs 135, which are secured in the cover plate 126. The outer ends of the studs 135 are provided with clamping nuts so that the plate 133 may be clamped in` any desired position against the cover plate 126.- 1t can now be'seen that the flange 124 on the right hand side of Fig. 6 is made discontinuous so that the plate 133 may extend out beyond t edge of the guide 121. The

pin 1,32 lies c ear of the side frame member 121, but the shoulder thereof, as shown at 131 in Fig. 6, projects through a slot in the side frame member, as can be seen in Fig. 4. A slot is shown in Fig. 4 at 136. By means of the adjustable plate 133 the trip 130 may be disposed at any selective point withinlimit so as to secure the desired closing of the valve at any point in the stroke of the plunger 2O within limits.

The opposite frame member1 120 is nslotted in a similar manner to permit the pipe 98 to pass therethrough and to be reciprocated with the plunger. Such a-slot is indicated at 137 of Fig. 4 for the plunger 19.

j valve 87.

A pin 138 is mounted in the adjustable plate 133 for stopping the counter-clockwise motion of the member 130 and a limit pin 139 limits the clockwise rotation of the same when the rear end of the pawl 115 rises and lifts the shoulder 131 of the member 130. i Obviously instead of a swinging trip member 130 a sliding member, such as shown at. 140 in Fig. 11 may be employed. The sliding member 140 has a tapered face, like a door latch bolt so thatv the rear end of the pawl 117 may push the member 140 into a recess against a spring 141 which spring projects the member 140 outwardly as soon as it is cleared by the pawl 117.

The means for opening the valve at the lower end of the stroke will now be de scribed. A swinging guide arm 142 is pivoted on a shoulder bolt 143 secured to thecover plate 126. The swinging guide 142 is provided with an adjustable weight 144 to cause the guide to swing counter-clockwise so that the end of the same engages the guide strip 128 (see Fig. 6). The weight 144 is in the form of an arm fastened at its inner'end vby a set screw to a stud 145 which stud passes through a slot in 'the coverljplate 126 and is ,secured to the guide 142 adjacent thev pivot the escape. of fluid past the valve 87. This valve seats with pressure andtherefore remains tight even under extreme pressure. As the spring111 throws the arm 109 in clockwise direction, as viewed in Fig. 6, the rollerl 110 engages the guiding strip 128 and follows downwardly along the same as indicated by the arrow 147, (see Fig. 6). The roller in its .descent pushesthe` guide arm- 142 out of the way, as shown in the dash and dot line on Fig. 6. In its downward stroke, the roller passes below the nose of the guiding arm 142 and immediately upon its upward stroke, asindicated by the arrow 148, is compelled to pass to thel left of the guide arm 142 wherebythe spring I111 is placed under tension, and at the same time the cam 104 is operated `to depress the push rod 88v for openin the The hook 116 of the paw 117 i drops into the notch 'holding the arm 109 and its connected parts in such position that thecvalve 87 is open during the complete upward stroke of the plunger 20. 'Thus, during the art of `the operation when the corresponding liquid column is not under pressure 'an escape is provided for fluid, particnlarl y gas, which may rise in the correspondingr column to escape out through the lateral and discharge pipe 101. Whereas thc evolution of gas occurs malnly 1n the discharge liquid column, I find 1t passageway 95, pipes 9G, 9S, flexible hose 99 advisable to provide an escape for gasor other fluid from the plunger which operates the inner liquid column, since the continued agitation of the liquid by reciprocationof the column tends` to evolve gas even though the same liquid is used over and over in the inner column.

The above described `valve 87 and its operating mechanism is alsouseful for controlling the displacement of thecorresponding plungers. i e

Thel displacement of the plungers is preferably made greater than the corresponding actual displacement of the motorpiston in the pump and the useful displacement may be A controlled by-suitable setting of the adjustable trip whereby a part ofthe actual displacement may be released and only the selected part utilized. i

This feature of controlling the effective displacement of the jack plunger, of plungers, is of importance, particularly in connection with the continued pumping of oil from a well. The 'capacity of the pump 1 at a given number of strokes per minute may be considerably in excess of the production ofthe well, that is, the rate at which liquid flows from the-well to the pump. It is desirable to operate the pump in such a manner that c it will pump' the liquid as rapidly as it flows into the well, but not any faster. If the pump had, for example, a complete stroke of ten foot traverse, it might be desirable to cut the stroke down to say six feet or four feet i or three feet, depending upon the rate of production of oil'in the well. ,By suitably settingthe point of closing of the stroke control valve, the jack plunger may be caused to displace into the column onlysufiicient 'liquid to make the shorter stroke of the pump desired to meet the rate of-production in the well. In this manner, the rate of pumping may be coordinated with the rate of production of oil in the well merely by controlling the point of closure of the stroke control valve or valves.

Variation of the actual displacement of the plungers may be secured by adjustment of the crank pin on the crank disc as previously explained.

The head mechanism may be used with 4the pump shown in my prior copending application', as indicated in Fig. 1, or it may be employed with modified forms ofthe same, as

illustrated diagrammatically in Figs. 2 and l cylinder 151.

top of a small motor cylinder 15() which forms a direct continuation of a larger motor Since the space between the pistons is not subjected to the actuating pressures these cylinders in effect constitute a single double acting cylinder andthe piston structure constitutes a single double acting piston. y

Suitable pistons 152 and 153 areeonnected by a rod 154 and are. also connected to the pump plunger 155 by a rod-156. A longitudinal passageway 157 extends from the space between -the pistons 152 and 153A through the pump piston 155 to the space below the latter, said passageway being controlled by a check valve 158 to permit evacui ation ofthe space between the pistons 152 and 153, said passageway also communicating der 10 to permit evacuation of any fluid from said latter space at the same time.

By this arrangement the depression of the liquid column in' the pipe 6 acts upon the piston 152 to make the discharge stroke of the pump piston 155. The area of the piston 153 issubstantially greater `than the area of the piston 152, so 4that under equal heads within the pipes S'and 6 there is a tendency for thel greater. force exerted on the. piston 153 to raise the connected pistons without addition'- al pressure beingl imposed by the corresponding pump plunger 19. Under these conditions I may dispense with the plunger 19 and employ only the plunger 20 connected to the pipe 6, depending solely upon the difference in area to make the suction stroke. In that event, the column in the pipe 6 could be maintained full of oil by placing a slight head of the same above the valve 87 and synehronism betwen the jack and pump maintained by the transfer valve 35.

. -I have shown in Fig. l3 a modified form of ent areas of the pistons-13V and 15 upon the ap- .115

plication of ressure to the discharge line.

In the jac which I have above described the gas release valves are located directly in the plungers, but it will be apparent to those skilled in the art that while this is the pre- 120 ferred method ofconstruction it is not essential tothe fundamental features of my invention. The provision of gas release Valves at suitable points in the columns operated syn.- chronously with the stroke`produeing meehanism to permit the escape of gas when the pressure on the corresponding column is released is the desired structure and action.

I do not intend to be limited to the deno tails shown and described. I

I claim :-l

1. Ina system of the class described, a cylinder, a piston therefor, means for reciprocating the piston at a predetermined constant rate, a let-off valve communicating directly with the cylinder for releasing excessive fluid from the cylinder and automatic means for opening said valve during a pre-determined portion of the stroke of said piston.

2. In a system of the class described, a cyl-v inder, a piston therefor, means for reciprocating the piston at a predetermined constant rate, a let-oli valve carried by the piston for releasing excessive fluid from the cylinder and automatic means for opening said valve during a pre-determined portion of the stroke of said piston.

3. In combination a vertical cylinder, a single acting plunger entering the top of the cylinder, said plunger having a passageway therethrough, a let-off valve for said passageway for releasing gas from the cylinder, and means for periodically opening and closing said valve.

4. In a device of the class described, a substantially vertical cylinder', a -plunger therefor entering the'upper 'end of the same, a

cross head for the plunger, a guide for the crosshead, said plungerhaving a passageway extending through the s ame to a point ad]acent the cross head,'a check valve conltrolling said passageway, a thrust rod for opening said check valve, a cam for operating said thrust rod, said cam being carried by the plunger, and means carried by the guide forv operating said cam.

A5. In combination, a cylinder, a plunger therefor, a cross head for the plunger, a

uide for the cross head, said plunger having a passageway therethrough, a valve controlling said passageway, and means within the plunger for holding said valve open during a pre-determined part of the stroke of said plunger, whereby the plunger idles during that part of the stroke;

6. In combination, a cylinder, a plunger.

therefor, a let-0H Valve for releasing fluid from the cylinderkduring a pre-determined portion of .the stroke sof the lunger, and means carried by the plunger or operating said let-off valve.

7. In combination, a cylinder, a plunger for the cylinder, a let-off Valve for the cylinder for releasing fluid from the cylinder` during a pre-determined portion of the stroke of the plunger, means tending at all times to close said valve, detent means for restraining said closing means, said detent means being carried by the plunger, and a relatively stationary trip member for re'- leasing said detent means.

8. In combination, a cylinder, a plunger therefor, a release valve operable during a pre-determined portion of thek stroke of the plunger to discharge fluid from the cylinder,

spring means carried by the plunger tending to close said valve, a detent for restraining said spring means, a relatively stationary trip for said detent, and guiding means for stressing said spring ymeans and causing the trip to engage with said detent means.

9. In combination, a liquid column adapted to be reciprocated, a motor cylinder communicating with one end of the column and having a piston adapted to be moved by a movement of said column, a second cylinder communicating with the yopposite end of said column, a piston therefor, and means operable on each return stroke of the latter piston for releasing gas at the top of the column.` v 10. In combination, aliquid column adapted to be reciprocated, a motor cylinder communicating with one end of the column,- and having a piston adapted to be moved by movement of said column, a second cylinder communicating ,With opposite end of said column, a piston therefor, means to move said second piston through a fixed stroke of greater displacement'than the displacement of 'said motor piston, and means operable upon each compression stroke of the second piston to release fiuid from the latter cylinder until the displacement of the remainder of the fixed stroke equals the displacement of the motor piston.

11. In combination, a pair of liquid columns adapted to be reciprocated, amotor member adapted to be reciprocated by saidl columns, a pump element actuated by said motor member, said pump element discharging liquid into one of'said columns, a pulsator for reciprocating said columns, a synchronously operated discharge valve for discharging from saidvone column the liquid pumped there into at each stroke, and a gas release valve operated during theoperation of the discharge valve for releasing gas from said one column of liquid.

12. In combination, a pair of liquid` col-- 13,'In combination, a conduit containing a column of liquid, a pulsator cylinder connected to one end of the conduit, a motor cylinder connected with the other end of4 the conduit, pistons for said cylinders, the pulsator piston having a stroke providing a greater displacement than the stroke of the motor piston, a let-off valve synchronously operated with the pulsator piston for releasl ing fluid from the pulsator cylinder during a pre-determined portion of the stroke of the pulsator piston, and a loaded release valve communicating with the conduit.

14. In combination, a pair of liquid containing conduits, pulsator cylinders communicating with the upper ends of the conduits, the lower end of said conduits being coaxial, a motor member separating the lower ends of the conduits and being reciprocable by reciprocation of the liquid columns in the conduits, means controlled b'y the motor element for imparti-ng an upward drift to the liquid in one of said columns, and cross connections between the condnits for synchronizing the motion of the motor member with the pulsator pistons, said connections including loaded check valves.

15. In combination, a pair of conduits, a pulsator communicating with the upper ends of the conduits, a motor member between the lower ends of the conduits, said conduits being adapted to be filled with liquid columns, a pump element operated by the motor member to discharge liquid into one of the conduits, a valve operated synchronously with the pulsator for drawing oil1 from said one column the liquid discharged thereinto by the pump, and cross connections betweenthe conduits for synchronizing the pulsator with the motor member, said cross connections including loaded check valves.

16. In combination, a conduit adapted to contain a column of liquid, a pulsator connected to the upper end of the conduit, a motor cylinder connected to the lower Aend of the conduit, a piston therefor, said pulsator piston having a iixed stroke, said motor piston having a fixed stroke of less displacement than that of the pulsator piston, and a let-off valve automatically opened during a part of the stroke of the pulsator piston, for

e letting olf gases and for securing the proper liquid displacement of the pulsator piston required to make a substantially complete stroke of the motor piston.

17. In combination, a pair of conduits adapted to contain liquid columns, a pulsator connected t0 the tops of s aid colmnns, and amotor; member adapted to be reciprocated by said liquid columns and disposed between the lower ends of the same, means controlled by said motor element for mparting an upward drift to the liquid in one of the columns, and means for synchronizing the motor member with the pulsator to secure substantially full stroke of the motor member each way. y

18. In combination, ajpair of ,conduits adapted to contain liquid columns, a pulsator connected to the tops of said columns, a motor member adapted to be reciprocated by said columns, and disposed between the lower ends of thesame, the lower ends being coaxial, means operable upon lack of synchro- 19. In an apparatus wherein pumping means at the bottom of a well is actuate by two reciprocating columns of liquid to pump liquid by imparting an upward drift to one of said columns, the combination of means toi-reciprocating said columns, discharge meansv controlling the discharge of liquid from the upwardly drifting column, and additional means for controlling the discharge of gases formed in said last mentioned column.

20. In an apparatus wherein pumping means at the bottom of a well is actuated by two reciprocating columns of liquid to pump liquid by imparting an upward drift to one of said columns, the combination of means for reciprocating said columns, discharge means controlling the discharge of liquid from the upwardly drifting column, and additional means eil'ective only during a predetermined portion o'f the operating cycle of the columns for discharging gases formed in said last mentioned column.

21. In an apparatus wherein v pumping means at the bottom 4of a well is actuated by two reciprocating columns of liquid to pump liquid by imparting an upward drift to one of said columns, the combination of means for alternately applying pressure to said columns for reciprocating the same, and gas release valves operated.synchronously with said last means for permitting the escape of gas from one of said columns when the pressure upon thatl column is released.

22. In an apparatus wherein` pumping means at the bottom of a well is actuated by two reciprocating columns of liquid to pump liquid by imparting an upward ldrift to at least one-of said columns, the combination umns, discharge means controlling the discharge of liquid from the upwardly drifting column and valve means carried by the piston means for permitting-the discharge of gases from at least one of said columns during a portion of each stroke of the piston.

28. In combination, a cylinder, a piston within the cylinder, means for reciprocating the piston, a column lof liquid terminating at the cylinder, liquid discharge means and gas discharge means for said column, valves for each of said discharge means, and means for opening and closing both of said valves in synchronism` with the piston.

24. In combination in a hydraulic jack, a pair of cylinders, pistons for said cylinders, means for operating said pistons in synchronism but in 4diierent phase, valve meansV controllingthe eiiective length of the working stroke of the pistons, and means for ad- 26. In a hydraulic jack, a` cylinder, a

plunger therefor, 'a crank for operating said plunger, a valve, means to hold said valve open during the initial part of the working stroke of the plunger to permit escape of the .contents of said cylinder, thereby controlling the eective length of the working stroke of the plunger, and means for closing said valve at a predetermined point `in the working stroke of said plunger, the major portion of the working stroke being subsequent to the closing of the valve.

27. In combination, a cylinder, a piston therefor, means to reciprocate the piston in the cylinder, there being an escape passageway for permitting escapeof the contents of the cylinder during a p-art of the compression stroke of the cylinder, a valve for said passageway for controlling the effective length of the stroke, said valve seating with pressure, a spring for applying said valve to its seat, and means comprising a cam'track and a cooperating roller governing the opening of said valve, said roller and cam track being relatively movable with respect to each other in synchronism with the movement of the piston.

28. In combination, a liquid column adapted to be .reiprocated, a motor cylinder communicating with one end ofthe? column and having a iston adapted to be moved by a movement o said column, a second cylinder communicating with the 'opposite end of said column, a piston therefor, means for making a fixed stroke'of the latter iston, and a synchronously operated valve or permittin escape of a'part'of the liquid between sai two pistons during a predetermined part of the pressure stroke of said latter piston.

A 29. In combination, a liquid column adapted to be reciprocated, 'a motor cylinder communicating with one end of the 'column and having a piston adapted to be moved by a movement ofsaid column, a second cylinder communicating with the opposite end of said column, a piston therefor, means for making a fixed stroke of the latter piston, a synchronously operated valve for permittin escape of a part of the liquid between sai two pistons during a predetermined part of the pressure stroke of said latter piston, and

means for adapting the dis lacement of i said second piston, in its cylin er to the displacement of the first piston comprising a stroke controlled valve and means operating synchronously with the second piston for controlling the operation of said valve.

30. In a deep well -pumping apparatus wherein liquid-is pumped by reciprocating two columns of liquid and imparting an upward drift to one'of said columns, means for intermittently applying pressure to one of said columns, valve means associated with each of said columns for discharging gases that may rise in the respective columns,

means controlled by the first named means for operating said valve means, and means for adjusting the point of operation of one of said valve means.

31. In a deep well pumping apparatus wherein liquid is pumped by reciprocating two columns of liquid and imparting an upv n ward drift to one column, means for intermittently applying 'pressure to one of the columns, valve means associated with each of the columns for discharging gases that may rise in the respective columns, means controlled by the first named means for operating said valve means, and means for independently adjustingthe point of operation of each of said valve means.

32. In a deep well pumping apparatus wherein liquid is pumped by reciprocating Atwo columns o f liquid and imparting an upward drift to one of said columns, means for intermittently applying-pressure to one of said columns, means for discharging liquid from the upwardly drifting column, and means independent of said last namedmeans for discharging gases that may rise in the upwardly drifting column.

33. In combination, a fluid pressure cylinder, a piston therein, means for reciprocating the piston to perform work on the iiuid in the cylinder, said pistor. having an opening therein to permit the free escape of the fluid therethrough upon the reciprocation ofl the piston, means for closing said openin during the working stroke of the piston an adjustable means for controlling the point.

of closure of said closing means whereby the effective len of the working stroke of the piston may e varied.

34. In combination, a cylinder a piston therein, said piston havin' a fixe stroke in the c llnder, and means or controlling the lengt of thel effective portion of the stroke, said means including a discharge passageway permitting the escape of fluid from the cylinder past the piston upon the reciprocation of the iston, valve means for closing and opening t e passageway, and means controlled in synchronism with the piston for controlling the valve, said last means including means for adjusting the point of operation of said valve means.

i my name this 17th da of September, 1927.

WILB R N. SQUIRES. 

